1. Field of the Invention
This invention relates to the construction and metallurgy of journal bearings, and more particularly to self-aligning, self-lubricating cartridge bearings of simple construction and low cost which can be marketed in the same manner as and used in place of more expensive ball bearings.
2. Description of the Prior Art
The art of journal bearings is well-developed. The following patents define the state of the art prior to the present invention.
My U.S. Pat. No. 2,761,746 granted on Sept. 4, 1956 described a self-contained package sleeve bearing which employed a sintered metal bearing material having a low PV rating, the PV rating being the product of the load on the bearing in pounds per square inch multiplied by the surface velocity in feet per minute.
My U.S. Pat. No. 2,922,682 granted Jan. 26, 1960 described a self-aligning and self-lubricating bearing of simple construction. The bearing was fabricated of sintered metal having porous properties which enabled lubricating oil applied to its outer surface to penetrate through the body of the bearing to the rotating motor shaft. The bearing was of spherical shape and rotated in its support and was self-aligning with respect to the motor shaft.
My U.S. Pat. No. 3,034,838 granted May 15, 1962 described a bearing permitting limited universal movement of the rotating motor shaft. The bearing was made of a porous bushing of bronze or like bearing material having a truncated spherical outer surface.
U.S. Pat. No. 3,317,256 to Ernest granted on May 2, 1967 described a bearing unit having a lubricant reservoir with a retainer for housing the lubricant, the retainer being adapted to be secured to relatively thin sheeted plates. The bearing was preferably an oil-impregnated sintered bronze.
My U.S. Pat. No. 3,655,249 granted on Apr. 11, 1972 described a self-contained, hydrodynamically lubricated packaged sleeve bearing having inner and outer races similar to the inner and outer races of a ball bearing. The outer race was rotatably journaled on the inner race by a plurality of arcuate aluminum bearing elements. A wicking material impregnated with special oil for lubricating aluminum bearing surfaces was packed in the bearing and the bearing was closed to contain and recirculate the oil. In the preferred embodiment, the aluminum metal bearing comprised a plurality of arcuate bearing elements cut and formed from an extruded aluminum wire or rod. The bearing elements were assembled between the inner and outer races to provide limited universal movement between the inner and outer races to compensate for shaft misalignment.
And finally, my U.S. Pat. No. 4,008,928 granted Feb. 22, 1977 described a self-aligning pod bearing assembly including a cylindrical casing forming a socket for a bead-shaped porous bearing which was urged against the socket by means of a resilient bearing retainer which fitted between a shoulder portion of the casing and the spherical bearing. The inside of the casing was filled with wicking material exposed through the bearing retainer to an oil slinger mounted for rotation with the shaft adjacent the end of the bearing contacted by the retainer. Another oil slinger was rotationally mounted on the shaft adjacent the other end of the bearing. In the preferred embodiment, the outer diameter of the casing was formed by the same casing member which formed the interior bearing socket thus insuring coaxiality of the nominal bearing axis and the outer diameter of the casing.